1. Technical Field
This disclosure relates generally to a friction brake system and, more particularly, to a brake pad for a friction brake assembly.
2. Background Information
A typical linear brake system for an elevator includes a plurality of brake actuation systems and a plurality of elevator brake assemblies. The brake actuation systems are attached to an elevator car that moves vertically within a hoistway along at least one elevator car guiderail. Each elevator brake assembly may include a solid metal brake pad affixed to a metal wedge-shaped brake shoe. Friction surfaces of the brake pads may engage respective opposing friction surfaces of the guiderail to slow or stop the relative vertical movement between the elevator car and the guiderail during emergency and/or overspeed situations. The term “overspeed” is used herein to describe a situation where the speed of the relative vertical movement is greater than, for example, 125% of an elevator's rated speed.
The engagement between the friction surfaces may subject the brake pads and the guiderail to relatively high temperatures. These high temperatures may cause the brake pads to fuse with (e.g., weld to) the guiderail, which may significantly increase the cost and time required to reset the linear brake system after each use. The high temperatures, as well as brake pad wear, may also decrease the coefficient of friction of such solid metal brake pads, which may significantly increase elevator car braking distances.